Abstract: When M observed signals xi(k) are sequentially inputted into a noise removing part 12 via M channels 11a of an input part 11 in time series, processing is sequentially performed on the observed signals xi(k) by singular value decomposition units 12a of N stages cascaded to one another. Specifically, the singular value deposition unit 12a of each stage separates M input signals into a signal subspace and a noise subspace by a singular value decomposition and extracts M output signals, which are signals over a time region, by orthonormal projection of the M input signals onto the separated signal subspace.

Abstract: An optical element that realizes light path conversion of transmitting light at low loss, allows easy incorporation of functions such as light convergence or the like, and can be easily made into a compact size includes upper and lower main surfaces of a light path converting element of a plane shape are facing each other, and a light incoming surface and a light outgoing surface are adjacent surfaces at about 90 degrees. A curved light path converting surface is formed so as to face the light incoming surface and the light outgoing surface. Light coming in from the light incoming surface repeats full reflection between the upper main surface and the lower main surface and goes on, and is reflected by the light path converting surface, thereby the light path thereof is converted, and light is ejected from the light outgoing surface.

Abstract: A defrosting controller for use with a refrigeration system determines calculating a frost melting period from the measurements of the evaporator temperature during defrosting by means of an evaporator temperature sensor, establishes a refrigerating operation rate which is the ratio of the period of the frost melting process to the (total) open period of an electronic motor-driven valve during the refrigeration, and then decides whether the next defrosting operation is to be skipped or not.

Abstract: A refrigeration showcase comprising a display case, a machine case and an air duct connecting the display case to the machine case, the display case comprising a display table for displaying commodities as placed thereon, a cover member openably covering the display table from above to define a commodity chamber above the display table and permitting the commodity chamber to be seen therethrough from outside, and an air passage member disposed under the display table and providing a cold air supply portion for supplying cold air therethrough to the commodity chamber and a cold air discharge portion independent of the supply portion for discharging cold air from the commodity chamber therethrough, the machine case comprising a case body, a refrigerator housed in the case body and providing a refrigeration cycle and a cold air circulating blower for supplying air cooled by the evaporator in circulation, the air duct having a forward air channel for transporting the cold air, and a return air channel independent